diff --git a/.github/workflows/test-eunomia.yaml b/.github/workflows/test-eunomia.yaml
index a44976d9..81a709ac 100644
--- a/.github/workflows/test-eunomia.yaml
+++ b/.github/workflows/test-eunomia.yaml
@@ -79,3 +79,7 @@ jobs:
       run: |
         ./ecc src/25-signal/signal.bpf.c src/25-signal/signal.h
         sudo timeout -s 2 3 ./ecli run src/25-signal/package.json || if [ $? = 124 ]; then exit 0; else exit $?; fi
+    - name: test 31 goroutine
+      run: |
+          ./ecc src/31-goroutine/goroutine.bpf.c src/31-signal/goroutine.h
+          # todo
diff --git a/.github/workflows/test-libbpf.yml b/.github/workflows/test-libbpf.yml
index 8da0881d..acc884f4 100644
--- a/.github/workflows/test-libbpf.yml
+++ b/.github/workflows/test-libbpf.yml
@@ -61,6 +61,10 @@ jobs:
       run: |
         make -C src/30-sslsniff
         sudo timeout -s 2 3 src/30-sslsniff/sslsniff || if [ $? = 124 ]; then exit 0; else exit $?; fi
+
+    - name: test 33 funclatency
+      run: |
+          make -C src/33-funclatency
     - name: test 35-user-ringbuf
       run: |
         make -C src/35-user-ringbuf
diff --git a/src/31-goroutine/goroutine.bpf.c b/src/31-goroutine/goroutine.bpf.c
index 6d1b7c6d..8ea21b9d 100644
--- a/src/31-goroutine/goroutine.bpf.c
+++ b/src/31-goroutine/goroutine.bpf.c
@@ -38,7 +38,7 @@ struct {
 SEC("uprobe/./go-server-http/main:runtime.casgstatus")
 int uprobe_runtime_casgstatus(struct pt_regs *ctx) {
   int newval = ctx->cx;
-  void *gp = ctx->ax;
+  void *gp = (void*)ctx->ax;
   struct goroutine_execute_data *data;
   u64 goid;
   if (bpf_probe_read_user(&goid, sizeof(goid), gp + GOID_OFFSET) == 0) {
diff --git a/src/31-goroutine/goroutine.c b/src/31-goroutine/goroutine.c
deleted file mode 100644
index 89c9ee90..00000000
--- a/src/31-goroutine/goroutine.c
+++ /dev/null
@@ -1,172 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0
-#include <argp.h>
-#include <signal.h>
-#include <stdio.h>
-#include <time.h>
-#include <sys/resource.h>
-#include <bpf/libbpf.h>
-#include "goroutine.h"
-#include "goroutine.skel.h"
-
-static struct env {
-	bool verbose;
-	long min_duration_ms;
-} env;
-
-const char *argp_program_version = "goroutine 0.0";
-const char *argp_program_bug_address = "<bpf@vger.kernel.org>";
-const char argp_program_doc[] =
-"BPF goroutine demo application.\n"
-"\n"
-"It traces process start and exits and shows associated \n"
-"information (filename, process duration, PID and PPID, etc).\n"
-"\n"
-"USAGE: ./goroutine [-d <min-duration-ms>] [-v]\n";
-
-static const struct argp_option opts[] = {
-	{ "verbose", 'v', NULL, 0, "Verbose debug output" },
-	{ "duration", 'd', "DURATION-MS", 0, "Minimum process duration (ms) to report" },
-	{},
-};
-
-static error_t parse_arg(int key, char *arg, struct argp_state *state)
-{
-	switch (key) {
-	case 'v':
-		env.verbose = true;
-		break;
-	case 'd':
-		errno = 0;
-		env.min_duration_ms = strtol(arg, NULL, 10);
-		if (errno || env.min_duration_ms <= 0) {
-			fprintf(stderr, "Invalid duration: %s\n", arg);
-			argp_usage(state);
-		}
-		break;
-	case ARGP_KEY_ARG:
-		argp_usage(state);
-		break;
-	default:
-		return ARGP_ERR_UNKNOWN;
-	}
-	return 0;
-}
-
-static const struct argp argp = {
-	.options = opts,
-	.parser = parse_arg,
-	.doc = argp_program_doc,
-};
-
-static int libbpf_print_fn(enum libbpf_print_level level, const char *format, va_list args)
-{
-	if (level == LIBBPF_DEBUG && !env.verbose)
-		return 0;
-	return vfprintf(stderr, format, args);
-}
-
-static volatile bool exiting = false;
-
-static void sig_handler(int sig)
-{
-	exiting = true;
-}
-
-static int handle_event(void *ctx, void *data, size_t data_sz)
-{
-	const struct event *e = data;
-	struct tm *tm;
-	char ts[32];
-	time_t t;
-
-	time(&t);
-	tm = localtime(&t);
-	strftime(ts, sizeof(ts), "%H:%M:%S", tm);
-
-	if (e->exit_event) {
-		printf("%-8s %-5s %-16s %-7d %-7d [%u]",
-		       ts, "EXIT", e->comm, e->pid, e->ppid, e->exit_code);
-		if (e->duration_ns)
-			printf(" (%llums)", e->duration_ns / 1000000);
-		printf("\n");
-	} else {
-		printf("%-8s %-5s %-16s %-7d %-7d %s\n",
-		       ts, "EXEC", e->comm, e->pid, e->ppid, e->filename);
-	}
-
-	return 0;
-}
-
-int main(int argc, char **argv)
-{
-	struct ring_buffer *rb = NULL;
-	struct goroutine_bpf *skel;
-	int err;
-
-	/* Parse command line arguments */
-	err = argp_parse(&argp, argc, argv, 0, NULL, NULL);
-	if (err)
-		return err;
-
-	/* Set up libbpf errors and debug info callback */
-	libbpf_set_print(libbpf_print_fn);
-
-	/* Cleaner handling of Ctrl-C */
-	signal(SIGINT, sig_handler);
-	signal(SIGTERM, sig_handler);
-
-	/* Load and verify BPF application */
-	skel = goroutine_bpf__open();
-	if (!skel) {
-		fprintf(stderr, "Failed to open and load BPF skeleton\n");
-		return 1;
-	}
-
-	/* Parameterize BPF code with minimum duration parameter */
-	skel->rodata->min_duration_ns = env.min_duration_ms * 1000000ULL;
-
-	/* Load & verify BPF programs */
-	err = goroutine_bpf__load(skel);
-	if (err) {
-		fprintf(stderr, "Failed to load and verify BPF skeleton\n");
-		goto cleanup;
-	}
-
-	/* Attach tracepoints */
-	err = goroutine_bpf__attach(skel);
-	if (err) {
-		fprintf(stderr, "Failed to attach BPF skeleton\n");
-		goto cleanup;
-	}
-
-	/* Set up ring buffer polling */
-	rb = ring_buffer__new(bpf_map__fd(skel->maps.rb), handle_event, NULL, NULL);
-	if (!rb) {
-		err = -1;
-		fprintf(stderr, "Failed to create ring buffer\n");
-		goto cleanup;
-	}
-
-	/* Process events */
-	printf("%-8s %-5s %-16s %-7s %-7s %s\n",
-	       "TIME", "EVENT", "COMM", "PID", "PPID", "FILENAME/EXIT CODE");
-	while (!exiting) {
-		err = ring_buffer__poll(rb, 100 /* timeout, ms */);
-		/* Ctrl-C will cause -EINTR */
-		if (err == -EINTR) {
-			err = 0;
-			break;
-		}
-		if (err < 0) {
-			printf("Error polling perf buffer: %d\n", err);
-			break;
-		}
-	}
-
-cleanup:
-	/* Clean up */
-	ring_buffer__free(rb);
-	goroutine_bpf__destroy(skel);
-
-	return err < 0 ? -err : 0;
-}